• Title/Summary/Keyword: culture

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Gamma Irradiation Effects on Conchospores of Porphyra Species 2. The Effects of High Gamma Irradiation on Germination and Growth of Conchospores of Two Varieties (김의 각포자에 대한 r-선의 조사효과 2. 두 품종의 각포자의 발아생장에 미치는 고선량 r-선의 조사효과)

  • KIM Joong-Rae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.1
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    • pp.52-56
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    • 1985
  • For the fundamental studies of radiation breeding in edible marine algae, the biological effects on conchospores of Porphyra species by gamma-irradiation were examined. Two varieties, Keun-cham-gim (Porphyra tenera Kjell. form tamatsuensis Miura) and Saga No.5, were chosen for this study, and their conchospores after r-irradiation($5.0{\sim}20.0$ KR) were cultured for 50 days. The results obtained were summarized as follows. 1. Gamma-irradiation in less than the dose of 20KR did not affect germination of conchospores, and almost all spores grew into two cells germ in 24 hours after irradiation, but withering germs were gradually increased in number according to higher exposure within 5 days old culture. 2. High irradiation caused the induction of giant cells, abnormal useless growth of hold-fast, lumpish thalli and callus-like lumpy tissues. 3. The liberation of neutral spores from young germs and carpospores from mature thalli were observed on the frond exposed at $10{\sim}20$ KR irradiation. All spores were normal in division and its size. 4. The best irradiation effect on growth of Keun-cham-gim was observed at 10 KR dose, whose growth-rates were $140\%$ in wet weight and $108\%$ in mean frond area, but only $48\%$ was recorded in wet weight at 20 KR exposure. Saga No.5 were in contrast with Keun-cham-gim, and their most growth-rate was $400\%$ in wet weight ($258\%$ in frond area) at 10 KR irradiation and the worst was $20\%$ at the dose of 20 KR. 5. The withering phenomenon to death by treatment of gamma-ray presented substantial difference between two varieties. Survival rate compared with control in Keun-cham-gim was $70.7\%$ at 20 KR, but that in Saga No.5 recorded $47.0\%$ at same dose. 6. Synthesizing the results of high and low r-irradiation, it was suggested tat high r-irradiation in more than 5.0 KR inhibited conspicuously the growth of germs derived from conchospores, and about half of them withered at 15.0 KR dose or more.

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Studies on the Availability of Marine Bacteria and the Environmental Factors for the Mass Culture of the High Quality of Rotifer and Artemia 1. Change of Fatty Acid and Amino Aicd Composition During Cultivation of Rotifer, Brachionus plicatilis by Marine Bacteria Erythrobacter sp. $S\;\pi-I$ (고품질의 Rotifer와 Artemia의 생산을 위한 해양세균 이용과 대량생산에 따른 환경인자에 관한 연구 1. Erythrobacter sp. $S\;\pi-I$에 의한 Rotifer, Brachionus plicatilis의 배양시 지방산과 아미노산 조성의 변화)

  • LEE Won-Jae;PARK You-Soo;PARK Young-Tae;KIM Sung-Jae;KIM Kwang-Yang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.3
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    • pp.319-328
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    • 1997
  • To develop a beneficial microbial feed for the cultivation of rotifer, Brachionus plicatilis, an aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ was isolated from marine structure at Haeundae beach in Pusan, Korea. Feeding effects of Erythrobacter sp. $S\;\pi-I$ on the growth of rotifer were analyzed comparing to other feeds such as PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. Erythrobacter sp. $S\;\pi-I$ contained more linoleic acid $(C_{18:3\omega3})$ and oleic acid $(C_{18:1\omega9})$ and amino acids than PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. The rotifer fed on Erythrobacter sp. $S\;\pi-I$ showed better effects than those fed on other feeds in the individual growth, size and weight. Also, the rotifer especially contained more eicosapentaenoic acid $(C_{20:5\omega3})$ and docosahexaenoic acid $(C_{22:6\omega3})$ in case of Erythrobacter sp. $S\;\pi-I$ feeding than the other feeds. In case of the feed of PSB and baker's yeast docosahexaenoic acid $(C_{22:6\omega3})$ did not show. In amino acid analysis, the rotifer fed on Erthrobacter sp, $S\;\pi-I$ showed more amino acid content comparing to those fed on other diets. Especially, arginine, isoleucine, histidine, lysine, methionine, phenylalanine, threonine, which are essential amino acid for fish growth, showed high contents. These results suggested that the aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ would be a beneficial microbial teed for the cultivation of rotifer.

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ISOLATION AND IDENTIFICATION OF BACTERIA FROM THE ROOT CANAL OF THE TEETH DIAGNOSED AS THE ACUTE PULPITIS AND ACUTE PERIAPICAL ABSCESS (급성 치수염 및 급성 치근단 농양의 치근관으로부터의 세균 분리 및 동정)

  • Lee, Yeon-Jae;Kim, Mi-Kwang;Hwang, Ho-Keel;Kook, Joong-Ki
    • Restorative Dentistry and Endodontics
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    • v.30 no.5
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    • pp.409-422
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    • 2005
  • The aim of this study was to identify the bacteria isolated from acute endodontic lesions by cell culture and 16S rDNA sequencing. The necrotic pulpal tissue was collected from 17 infected root canals, which were diagnosed as being either an acute pulpitis or acute periapical abscess. Samples were collected aseptically from the infected pulpal tissue of the infected root canals using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing 500 ul of 1 XPBS. The sample solution was briefly mixed and plated onto a BHI-agar plate containing $5\%$ sheep blood. The agar plates were incubated in a $37^{\circ}C$ anaerobic chamber for 7 days. The bacteria growing on the agar plate were identified by 16S rRNA coding gene (rDNA) cloning and sequencing at the species level. Among the 71 colonies grown on the agar plates, 56 strains survived and were identified. In dental caries involving the root canals, Streptococcus spp. were mainly isolated. Actinomyces, Clostridia, Bacteroides and Fusobacteria were isolated in the periapical lesion without dental caries. Interestingly, two new Actinomyces spp. (ChDC B639 and ChDC B631) were isolated in this study. These results showed that there was diversity among the species in endodontic lesions, This suggests that an endodontic infection is a mixed infection with a polymicrobial etiology. These results may offer the bacterial strains for pathogenesis studies related to an endodontic infection.

Distribution Patterns and Ecological Characters of Paulownia coreana and P. tomentosa in Busan Metropolitan City Using MaxEnt Model (MaxEnt 모형을 활용한 부산광역시 내 오동나무 및 참오동나무의 분포 경향과 생태적 특성)

  • Lee, Chang-Woo;Lee, Cheol-Ho;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.2
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    • pp.87-97
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    • 2017
  • Paulownia species has long been recognized in Korean traditional culture and the values of the species have been researched in various focuses. However, studies on distribution and ecological characteristics of the species are still needed. This study aimed to identify distribution trends and ecological characteristics of two Paulownia species in Busan metropolitan city using the MaxEnt model. The MaxEnt model was established based on the environmental factors such as positioning information of the Paulownia species, topography, climate and degree of anthropogenic disturbance potentiality (ADP), which was collected in the on-site research. The study verified that the accuracy of the model was appropriate as the AUC value of Paulownia coreana and P. tomentosa was 0.809, respectively. In terms of the distribution trends of the two Paulownia species in the research area depending on the distribution model, they were both mainly distributed in downtown where built-up area and bare ground were densely concentrated. The potential distribution area of the two species was identified as $137.4km^2$ for P. coreana and $135.0km^2$ for P. tomentosa. The distribution probability was high in Jung-gu, Dongrae-gu, Busanjin-gu and Yeonje-gu. As a result of the analysis on contribution of the environmental factors, it was turned out that the degree of anthropogenic disturbance potentiality (ADP) contributed to distribution of P. coreana and P. tomentosa by about 50%, and the contribution of the environmental factors had a positive correlation with the degree of ADP. The elevation had a negative correlation with both the two species, which was considered because the species must compete more with native species in natural habitats as the altitude above sea level rises. The research findings demonstrated numerically that the distribution of P.coreana and P. tomentosa depended on artificial activities, and indicated the relevance with the Korean traditional landscape. These findings are expected to provide meaningful information in using, preserving and restoring Paulownia species.

A Study on the Present Condition of Four-Year University Curriculum for Introducing NCS Landscape Architecture (NCS 조경 분야 적용을 위한 4년제 대학 교육과정 현황분석)

  • Lee, Chang-Hun;Kim, Kyou-Sub;Lee, Won-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.3
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    • pp.134-147
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    • 2019
  • The purpose of this study was to analyze the functional unit system of NCS landscape field for correction and supplementation of NCS landscape field and the contents of the four-year college landscape course subject. First, 24 unconsolidated four-year universities were selected, and FGI was conducted and verified for 816 courses in 24 universities. The results of the study are summarized as follows, with three sections three, nine divisions and 65 sub-category. First, landscape design subjects accounted for 40.0% of the subjects organized by four-year universities. In addition, the ratio of 12.9% for ecological landscape, 11.3% for landscape construction, 10.2% for others, 10.0% for landscape information, 6.6% for landscape culture and 3.7% for landscape management was surveyed. Balanced and efficient modification and reinforcement of NCS is required in the future. Second, 10(18.9%) units with matching NCS performance criteria and educational objectives were found to be capable of different units(18.9%), 15(28.3%), and 37subjects with inconsistent NCS unit capability (56.9%). Third, looking at the criteria for the reference of each unit of capability presented by the NCS, it is deemed that one unit of capability should be organized separately to improve the practical ability, since it includes the contents of basic knowledge learning. Fourth, the objectives pursued on the basis of the contents of the NCS capability unit and four-year college curriculum were developed by focusing on the development of unit capabilities in the field of landscape construction and landscape management compared to the field of landscape design. It has been shown that a balance is needed for future development. This study is intended to put forward further research that re-examine specific curriculum assessment criteria that have not been classified in the course of classifications based on the curriculum handbook, which excludes interferences from each school.

A Characteristics of 16 Scenes of Chilitan and Management of Chiltanjung, Milyang (밀양 칠탄정 경영과 칠리탄 16경의 경관특성)

  • Kim, Soo-jin;Jung, Hae-Joon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.3
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    • pp.22-36
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    • 2019
  • This research identified landscape characteristics of Chilitan(칠리탄) area, which had been managed by Son Giyang(1559~1617, p. Ohhan), in order to understand the political viewpoint and ideal landscapes, sought after by Confucian scholars in the 16~17th century. As the research method for the interpretation of each scene's spatial strucutres and meanings, paintings and poems in Chiltanjungsipyukgyeongdo(the Paintings of the 16 Scenes of Chiltanjung Area) were analyzed, which were followed by the on-site survey. Son lived hermit life with the nature after he decided to retire into the country for the chaotic political environment in the 4th year of Gwanghaegun's reign. Admiring Eum Jareung(B.C. 39-41, p. Eumgwang)'s hermit life, he named a headstream to Chilitan, erected pavilion and made place for angling by the stream, as Eum did in the hermitage. However he worried the king and royal politics in spite of his hermit life, which showed his political viewpoint of Confucianism. In addition, every column of buildings in the garden was named in order to imply both thoughts of Neo-Confucianism and Idleness Naturalism, which highlight a moral training and being comfortable amid poverty and taking pleasure in and honest life style. The present landscape of wonlim could be back to 1936, where Unganru, Byeokripjae and Chiltanjung are surrounding Eupcheondang. Chines character, such as Jimamsuseok, Giam, Ohhansonsunseongjanggujiso and Jogi, are inscribed on the rocks in the landscape garden, from which placeness could be inferred. According to the record of the construction, pine, fir, paulownia, ginkgo, peach trees, bamboo and lotus were planted, and ginkgo, bamboo, crape myrtle, pine and chestnut tress are still living in the garden, which mean plants had been planted in the light of their practical values as well as symbolic meanings. The method for describing 16 scenes of Chiltanjung could be characterized to the structure of 「Place+Scene(a particural activity, event, or action), and these placeness could be analyzed by categorizing the scene to near, middle and far views. Each scene symbolically presents a hermit, noble man, Taoist ideology, homeland, or peacetime, which were adpoted to depict landscapes of Chiltanjung area as the Confucian utopia.

Studies on the Tissue Culture of Some useful woody species (유용수종(有用樹種)의 조직배양(組織培養)에 관(關)한 연구(硏究))

  • Kim, Jai Saing;Lee, Sam Sup
    • Journal of Korean Society of Forest Science
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    • v.43 no.1
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    • pp.6-13
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    • 1979
  • In order to substract the time and cost of propagation for inducing the haploid plants per each species. 500 anthers of late uninucleate microspore on early binucleate microspore stage of Robinia pseudoacacia (Fuel tree) Punius granatum (Ornamental tree). Aleurites fordii (Faty tree) and Styrax japonica (Silvicultural tree) were cultured on the modified Murashige and Skoog's medium supplemented with Kinetin, 2.4-D and NAA as growth regulators. And I observed the samples of cultured anthers under the microscope which were made by Microtoming method and Paraffin method. The results were summarized as follows: 1) Among 500 cultured anthers per each species, anther numbers inducing the diploid callus were as follow: Styrax japonica 20 (4% for the species total); Aleurites fordii 10 (2% for the species, total) and Punica granatum 45 (9% for the species total) were showed. 2) 2n Callus were induced from anther wall. but haploid callus were induced from anther locule. 3) Haploid callus were induced only in 25 anthers (5% for the species total) of Robinia pseudoacacia. 4) These haploid callus were not originated from body cell of anther wall tissue, but from reduced microspores, 5) Since already reported many herbaceous haploid plants were induced from the callus which were originated from reduced microspores, I conclude that the anther of woody plant which induced the haploid callus also will be cultured haploid plant.

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Effect of Scrapping Aerial Mycelia and Light on the Production of Macroconidia and Chlamydospores of Cylindrocarpon destructans Causing Root Rot of Panax ginseng (기중균사 제거와 광처리가 인삼 뿌리썩음병균 Cylindrocarpon destructans의 대형분생포자 및 후막포자 생성에 미치는 영향)

  • Cho Dae-Hui;Yu Yun-Hyun;Ohh Seung-Hwan
    • Journal of Ginseng Research
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    • v.23 no.3 s.55
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    • pp.123-129
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    • 1999
  • Under the light condition of 25,000 Lux (12 hrs dark and light cycle) with scrapping treatment of aerial mycelia of Cylindrocarpon destructans on potato dextrose agar (PDA), V-8 juice agar, and ginseng extract agar, production of the macroconidia was increased to $3.7\~8.1$ fold over them produced in the dark. They were also produced $7.7\~18.0$ times more in the liquid cultures under the light condition than under the dark as well. PDA and V-8 juice agar among the tested were the best for the macroconidium production. On PDA, 1,585 $macroconidia/mm^2$ were produced under the light of 25,000 Lux with scrapping treatment of aerial mycelia of C. destructans, which is 3.2 and 1.4 times more than those produced under 3,000 and 10,000 Lux, respectively. Meanwhile, $20\~99$ macroconidia/$mm^2$ were produced by the non-scrapping under the light condition between 3,000 Lux and 25,000 Lux. The macroconidia were, however, lysed at $6\~7$ days after being incubated under the above range of the light. They were consisted of $1\~3$ cells in a macroconidium while $69.4\~100\%$ of them were the two-celled and the number did not seem to be affected by either the scrapping or the light. Production of chlamydospore converted from mycelia of C. destructans seemed to be promoted by the light and the scrapping as well. The 1,285 chlamydospres/$mm^2$ were produced with the light (25,000 Lux), which is 2.8 and 1.2 times more than those with 3,000 and 10,000 Lux, respectively. Scrapping the aerial mycelia of the cultures increased the chlamydospore formation to 1.9, 2.5 and 1.4 times more than the non-scrapping under the light intensity of 3,000 Lux, 10,000 Lux, and 25,000 Lux, respectively. On PDA, 1 to 8 chlamydospore(s) per catena were formed by all treatments tested and $34.2\~58.9\%$ of them was a single chlamydospore, However, the numbers was affected by neither the light ($3,000\~25,000$ Lux) nor the scrapping the aerial mycelia.

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The Influence of the Restrictions in Chinese economic growth on Korean commercial environment (중국 경제성장의 제약요인이 한국 통상환경에 미치는 영향)

  • Shong, Il-Ho;Lee, Gye-Young
    • International Commerce and Information Review
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    • v.15 no.4
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    • pp.457-479
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    • 2013
  • Through a Chinese rise, Chinese dream is actualizing as the world's great power. According to outlook of World Bank and IMF, Around 2030 China will be a great power bigger than America's economic power. The rise of China will give a huge impact to the whole world. China expands her influence through a global manufacturing base and a global market. To actualize 'Peaceful Rise' Strategy, China has many constraints. Chinese society is facing many difficult social problem due to side effects of a rapid development. Such as the spread of corruption, the severity of wealth gap, environmental degradation and energy shortage. Internationally there are containment from hegemon so-called 'China threat' dispute, Taiwan issue and territorial disputes. Western countries are hostile to China for two reasons. Based on expectations, one is China's socialist system and the other is the rising China which will compete for supremacy with Europe and America. Recent emergence of Chinese nationalism and the containment of the neighboring countries are also serious limiting factors. Domestically they have the rampant corruption in the bureaucracy, weakened capacity of Communist rule, wealth disparity due to the discriminatory economic development strategy, seriousness of rural problem, social instability, lack of social security systems and the development gap between the eastern coastal areas and western inland areas, ethnic minorities problems, the constraint of sustainable development issues due to lack of resources, environmental pollution and energy constraints. Like the former Soviet Union, China may face a dismantlement. After the rise, China may encounter possibilities of a war between great powers or a collapse of Chinese society caused by deepening internal conflict. Serious economic polarization would make peasants and urban workers, who are social vulnerable people, to turn their back to communist party and threaten the justification and the appropriateness of the ruling communist party. Chinese government will think internal system security threat is more formidable risk factor than a system security threat from the hegemon. The decline of great country comes from internal reasons rather than external reasons. To achieve peaceful rise, unification with Taiwan is an essential prerequisite. Taiwan issues are complex problems which equipped with international and domestic factors. Lack of energy resources, environmental pollution in China will bring economic crisis to Korean enterprises. Important influence to Korean economy will be a changeover of the method in economic development. It will turn the balance of investment and consumption, GDP-centered growth to consumption and environment-centered growth. Services industries including finance, environment, culture, education, health care and social welfare will grow. Change in China's growth model will give a great challenge upon the intermediate goods industry in Korea. Korea should reduce the portion of machinery, automotive, semiconductor, steel and chemical-centered export industry to China, and should increase the proportion of the service industry.

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A Study on the Relationship between the Tax Evasion Factors and the Tax Evasion Inclination of Value Added Tax in Korea (부가가치세 포탈요인과 포탈성향에 관한 실증적 연구)

  • Kim, Beom-Jin;Ham, Young-Bok
    • Korean Business Review
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    • v.14
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    • pp.1-30
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    • 2001
  • To prevent the VAT evasion and to form a sound VAT paying culture, we can draw the policy directions for government as follows: First, it is necessary to strengthen the tax supervision of small business and the administration of tax sources of cash-income industry. Second, the tax-deductible rate of the received tax invoices should be increased in a short-term base, and a simplified taxation system should be abolished in a long-term base. Third, in cases a trader has not received a tax invoice, an additional tax should be applied. Forth, to issue the tax invoice faster and conveniently, it is requested to introduce a new system which issues electronic card of registration when a businessman applies for his/her business registration. Fifth, to make tax standard transparent, it is desirable to punish the violator, relating to credit card regulations, stricter than present and to enforce the electronic bookkeeping. Sixth, for the reduction of noncompliance rate and creating a climate for autonomous, faithful tax return, it is necessary to expand and intensify tax investigation. And also it is necessary to make the level of penalty tax higher up and the level of criminal punishment less down, to keep up tax audit coverage. Seventh, a trader who is eligible for simplified taxation, whose tax base is under 12,000 thousand won, should not be required to pay the value added tax. But it is desirable to cut down them for the fairness of tax burden. Eighth, the effective date of the revised tax law should be fixed. Ninth, it is necessary to reinforce publicity and to educate on tax system and administration, for reducing tax evasion or tax avoidance and encouraging faithful tax return. Tenth, as the tendency of VAT evasion of distribution industry turns out to be the highest, it is requested not only to intensify tax administration on them but also to establish system and incentives, for introducing information system in distribution industry(introducing POS system, computerization of transaction record, establishing EDI between traders).

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